Study design issues and early stage non-small cell lung cancer.

The most common type of clinical trial in oncology enrolls patients with advanced disease. End points for phase II trials in advanced disease typically include response rate or time to progression, based upon the presumption that these may serve as surrogates for the ultimate end point of improved survival. Unique problems arise with the design of adjuvant trials, for which response rates clearly are not appropriate end points. In addition, survival is much longer, making rapid completion of phase III trials difficult. For lung cancer, the proportion of patients with stage I and II disease is much lower than with other types of cancer, and the absolute number of these patients is relatively low. To conduct large adjuvant trials in lung cancer more efficiently, we need to optimize our trials as much as possible. "Targeted therapies," by definition, inhibit a specific target, thus offering the theoretical advantage of enriching the patient population by restricting enrollment to patients whose tumor expresses the target of interest. Education of health care professionals regarding the benefits of adjuvant therapies, to decrease a sense of nihilism and to increase referrals, and international collaborations may also be necessary to increase accrual.